CIP and SIP Procedures Applied in Food, Beverage and/or Pharmaceutical Manufacturing, Processing and/or Packaging Facilities
The term Cleaning-in-Place (“CIP”) has been adopted as the determinant descriptive that refers to a process when an item of immovable food, beverage or pharmaceutical manufacturing, processing and/or packaging equipment may be deemed to be both clean and sanitary. The reference to “food, beverage and/or pharmaceutical manufacturing, processing and/or packaging system and/or equipment” in this specification refers to any given product type and includes all raw, intermediate and final product contact surfaces where the potential for accumulation of product residue is possible, including, but not limited to, fixed and removable components of the ingredient and/or product storage, manufacturing, processing and/or packaging system or subsystems thereof, including related equipment.
The measures to verify the efficacy of a CIP process have predominantly been aligned to the assessment of the sanitary or microbial contamination status of the equipment after a CIP procedure, and these measures have become the indirect yardstick for determining whether the cleaning component of the CIP procedure has been effective in terms of removal of residual product soils. However, because industrial food, beverage and pharmaceutical processors have adopted the verification of the cleaning and sanitizing processes to the tools and measures directly associated with determining the presence of microbial contaminants, this approach potentially permits tenacious soils (organic and inorganic residues), such as flavourants, colourants and complex biological materials, to persist in the manufacturing, processing and/or packaging infrastructure, albeit in a sanitized or sterile state.
Notwithstanding the capacity of these organic and inorganic residues to vest and consolidate in difficult-to-clean places, they also serve as the foundation for a biofilm matrix to form, wherein a microbial consortium will readily proliferate. In addition, the persistence of tenacious soils, such as carbohydrate or oil-based flavourants and colourants, will compromise further batch-packaging and overall product integrity. The persistence of organic soils provides a nutritional platform for microbes to flourish and incomplete cleaning will inevitably result in widespread microbial contamination, concomitant product spoilage and premature deterioration. Furthermore, this largely undetected microbial contamination of consumer products may also increase the potential for contamination of such consumer products with microbes which are human pathogens and which would have heightened adverse public health implications.
By actively realigning the cleaning and sanitization process of a given industrial food, beverage and/or pharmaceutical processor to the recognition of the likely profile of residual soils that would be encountered in all equipment, and then tailoring the choice of cleaning and sanitizing remedies best suited to optimizing the CIP and Sanitizing-in-Place (“SIP”) procedures, one has a substantially greater likelihood of delivering consistently reliable CIP and SIP procedural outcomes.
It is known in the industry that, to use dedicated colorimetric indicators to evaluate the presence or absence of organic soils in various intermediate rinse solutions, is a critical step in verifying whether a detergent agent used has effectively removed residual soils, prior to embarking upon a subsequent sanitizing intervention. Such colorimetric indicators also serve to guide the choice of detergent agent relative to a product soil profile and equipment design, the application protocol and most importantly, the profile of organic and inorganic soils likely to persist after production and packaging.
Current colorimetric indicator assays for organic compounds rely primarily on formulations using permanganate chemistry and its well established reactivity when mixed with organic soils in an alkaline environment. However, the problems associated with permanganate stability are also well established. As a potent oxidizing agent, permanganate's stability, once exposed to environmental conditions (primarily oxygen), results in a rapid breakdown of the permanganate molecule with rapid loss of reliable colour-based reactivity when mixed with organic compounds. It is for this reason that all current permanganate colorimetric indicators are available as solid or powder formulations only, packaged in and under corrosion, light, atmosphere and moisture sensitive materials and conditions. All formulations are applied on-site to process water used for cleaning of food, beverage and pharmaceutical equipment and do not display any extended stability once re-constituted with water.
Previous patents using permanganate-based chemistry, such as Thonhauser et. al. (U.S. Pat. No. 8,083,966) and Fischer (U.S. Pat. No. 7,867,339), have described products and procedures where the permanganate molecule forms a component of a cocktail of cleaning and disinfecting compounds. The reconstituted formulation is applied into the internal reticulation of a beverage processing and packaging system and the colour changes in the cleaning and disinfecting solution are a reflection of the efficacy of the latter compounds in effecting the required cleaning and sanitation of the equipment.
This invention serves to make available a reliable colorimetric indicator diagnostic tool, which has an extended shelf life when stored under optimal storage conditions. Moreover, the invention seeks to provide a diagnostic tool and a method of using the same that will re-educate plant operators of the need to separate CIP processes from SIP processes, and which will readily assist in evaluating and improving current CIP practices, as well as trouble-shooting instances where inconsistent packaged product quality may result in compromised brand integrity and equity.
Historical reliance on diagnostic tests (e.g. Clinistix) and ATP systems have been shown not to be repeatable in guaranteeing optimal removal of organic residues from food, beverage or pharmaceutical manufacturing, processing and/or packaging equipment. To date there is no dedicated and reliable measure to quantify whether a CIP process has been effective in removing such organic residues.
Microbial Biofilms
The term “microbial biofilm” describes the presence of a variety of microbial cells which are adherent to a contact surface and enclosed in a matrix of Extracellular Polymeric Substances (“EPS”) in an aqueous environment. Biofilm has been reported to comprise of consortia of micro-colonies of different species of microbial cells (≦15% by volume) and a non-cellular matrix of various predominantly organic components (≦85% by volume) which confers structural stability. The structure of a matrix of EPS has been shown to comprise primarily of polysaccharides and, to a lesser extent, proteins, nucleic acids, peptidoglycan and lipids. The polysaccharides have been shown to consist of homo-polymers, such as cellulose, as well as a wide variety of monosaccharide carbohydrate compounds, including glucose, fructose, galactose and mannose, amongst others. Teichoid acids, comprising glycerol and glucose, are also encountered.
The significance of a confirmed biofilm presence in any aqueous environment is that microbial cells, or microbes, present in the EPS matrix serve as a source of continuous microbial contamination for the aqueous system. In addition, impermeability of the EPS matrix confers a significant degree of protection for the varied microbial populations against biocidal agents that may be used to control microbes in the same environment. Finally, the EPS matrix provides a nutritional platform to support and promote the growth of various microbes.
The biofilm structure and appearance is dictated by many factors, including the nutritional profile of the aqueous environment, oxygen tension, as well as the flow rate of the liquid across the surface of the biofilm. As biofilms grow and mature, portions will break free from a parent biofilm, thus spreading both microbes and aspects of the EPS matrix to other aspects of the aqueous liquid system.
Water used in the preparation of CIP procedures, SIP procedures and final rinse solutions in food, beverage and pharmaceutical industries, may be sourced from municipal supplies or alternatively prepared on-site in water treatment plants, specifically geared to preparing water solutions of known quality and sanitary status. In these water treatment facilities, the presence of biofilm serves to reduce the efficiency and yield of process equipment such as sand filters, ultra- and nano-filtration and reverse osmosis membrane systems. In addition, the continuous presence of microbial biofilms would serve to contaminate the treated water with microbes.
Where the aqueous solutions containing dislodged and free-floating microbes and aspects of the EPS matrix are used in cleaning and sanitation procedures in food, beverage or pharmaceutical manufacturing, processing and/or packaging equipment and facilities, there is a significantly heightened risk of both further downstream contamination of the manufacturing, processing and/or packaging equipment with organic soils and microbes, as well as microbial spoilage of food, beverage and pharmaceutical products produced and packaged with the equipment.
Moreover, as part of a filtration process to treat raw water from open water bodies (such as seawater, dams, lakes, and the like) for the production of potable water for human consumption, the specific requirement to control dissolved organic compounds is an inevitable consequence of the overall process. These complex organic compounds comprise primarily of humic and fulvic acids and differ substantially in size and molecular mass from 300 000 to 2000d respectively.
Membrane filtration systems used in potable water treatment plants are designed to exclude these organic compounds from the final water product and selectively to remove high molecular mass compounds first through ultra-filtration systems (“UF”), which allows smaller molecular mass organic compounds to pass through the membranes for further processing in subsequent filtration stages. However, the presence of progressively increasing concentrations of low molecular mass organic compounds in intermediate processed water streams provide the fundamental nutritional building blocks necessary to support and sustain microbial growth in the system. This results in incremental bio-fouling of the membrane filtration systems and all supporting infrastructure.
The invention seeks to provide a diagnostic tool and a method of using the same as a pre-screening aid to verify the absence of organic contaminants normally associated with biofilm from prepared rinse water prior to its use as a final rinse solution after both CIP and SIP procedures. The invention further seeks to provide a diagnostic tool and an associated method for use thereof to identify the molecular mass of organic contaminants in a water sample.